Los Angeles County West Vector & Vector-Borne Disease Control District

Locations of Lyme Positive Ticks

It should be noted that only a few sites have been
confirmed as positive. However, the species of tick, Western Black-Legged
tick (Ixodes pacificus), that carries the bacterium for Lyme Disease
has been found in other areas
throughout the District. Western black-legged ticks have been found in 55
of 58 counties in California. On average, only about 1-2% of the adult Western
Black-Legged ticks in California are infected with the bacterium that causes
Lyme disease. In some areas north of the San Francisco Bay Area, up to 5%
of the adult ticks and 14% of the nymphal ticks may be infected: this is still
much lower than the northeastern U.S. where 30-60% or more of the adult ticks
are infected.

Sites
where ticks positive for the Lyme disease bacterium have been found in the District

Click on the links below to
view results for Western Black-legged ticks collected in our District